Map type

Should there be a map type?

I have a structure that looks like this:

```
Item {
title {
de_DE,
fr,
pa,
.....
}
}
```

The point here is that the number of language strings might be arbitrary. I find this hard to model using GraphQLObject, because:
1. The number of locales is undefined. While the resolver could handle this dynamically, I think it's a problem in Relay that the schema cannot reflect these dynamic fields.
2. I would like to query all the existing locales, which isn't allowed, it seems ("must have a sub-selection").

If I make my GraphQL server return a JSON object for "title", the Relay client doesn't complain (although maybe shouldComponentUpdate breaks), but I think I'm skirting by here. At the very least, I think I couldn't generate a schema that confirms to the spec.